March Challenge 2017
Xenny and Alternating Tasks, Bear and Extra Number
May Challenge 2017
Chef and his daily routine, Courses in an university, Median of adjacent maximum numbers
August Long Challenge 2017
Chef and Rainbow Array, Chef and Mover, Greedy Candidates
October Challenge 2017
Max Mex, A Balanced Contest
November Challenge 2017
Chef goes Left Right Left, Villages and Tribes, Periodic Palindrome Construction
December Challenge 2017
Chef And his Cake, Penalty Shoot-out
September Cook-Off 2017
Statistics Construction, Subsequence Equality
November Cook-Off 2017
Random Pair, Online Chess
September Lunchtime 2017
Chef and Cook-Off Contests
January Challenge 2018
Maximum Score, Rectangle, Partition the numbers
January Cook-Off 2018
Multiple of 3, Survive in ChocoLand
February Challenge 2018
Chef And The Patents, Permutation and Palindrome, Car-pal Tunnel, Chef And His Characters
May Challenge 2018 Division 2
Mighty Friend, Minimum Deletions, Xor Again
February Challenge 2019 Division 2
Chef and Magical Jars, Chef and Secret Ingredients, Appy and Contest, Deputy Chef
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